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A Phased Aerodynamic Optimization Method for Compressors Based on Multi-Degrees-of-Freedom Surface Parameterization

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Journal of Thermal Science 2021年第6期30卷 2071-2086页

作者： CHENG Jinxin YANG Chengwu zhao shengfeng Key Laboratory of Light-duty Gas-turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100049China

High-fidelity aerodynamic optimization of compressors is afflicted by the"curse of dimensionality",which limits its engineering *** paper proposes a new multi-degrees-of-freedom(MDOF)surface parameterization method that combines the characteristics of conventional surface parameterization methods,low-dimensionality and surface smoothness,with the advantages of design flexibility and ease of *** proposed method is applied to the high-fidelity aerodynamic optimization of *** optimized solution is obtained within 111 h by combining a phased optimization strategy based on the idea of modal *** explore a better way of setting the control variables of the blade body,two methods of varying the control points of the suction and pressure surfaces,independent change and synchronous change,are *** change has better flexibility,and under the condition of satisfying the constraints,it increases the efficiency at the design point by 2.2%and the surge margin by 0.5%.This demonstrates the effectiveness of the proposed method in the high-fidelity aerodynamic optimization of *** also provides technical support to solve the"curse of dimensionality"problem.

关键词： surface parameterization aerodynamic optimization compressor blade phased strategy

Exploring the intention of Using Aspirated Cascade to Replace Tandem Cascades

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Journal of Thermal Science 2010年第5期19卷 390-396页

作者： shengfeng zhao Jianfeng Luo Xingen Lu Junqiang Zhu Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 Graduate School of Chinese Academy of Sciences Beijing 100190 China Shanghai Electric Power Generation Equipment Co. Ltd. Shanghai Turbine Plant Shanghai 200240 China

In the present paper,computational fluid dynamics(CFD) simulations were executed to exploring the intent of using aspirated cascade to replace tandem ***,the ONERA tandem cascades were investigated,and the performance of the cascades at the design point were listed,such as diffusion factor,total pressure loss coefficient,deviation angle *** replacing the ONERA tandem cascades,a new cascade was designed with the codes BLADEGEN developed by the *** quasi 3-D calculations were carried out using the collection of programs for cascade analysis and design,*** cascade was analyzed and designed by using this *** the cascade was simulated and analyzed by commercial CFD *** is found there is an obvious separation on the suction *** on the 3D CFD simulation results of the cascade without aspiration,an aspirated cascade was designed by introducing a slot on the suction *** performance of the aspirated cascade was investigated and compared with the tandem cascades,indicated that under the same inlet condition,the total pressure loss of the single row aspirated cascade was less than that of the tandem cascades,and the outlet static pressure is higher than that of the tandem ***,the different suction slot location,suction width and suction mass flow are studied for the aspirated cascade.

关键词： tandem cascades aspirated cascade flow control boundary layer separation

An Experimental Study of Separation Control on Ultra-Highly-Loaded Low Pressure Turbine Blade by Surface Roughness

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Journal of Thermal Science 2015年第3期24卷 229-238页

作者： SUN Shuang LEI Zhijun LU Xingen zhao shengfeng ZHU Junqiang Civil Aviation University of China Institute of Engineering Thermophyiscs Chinese Academy of Sciences

An experimental study is conducted to improve an aft-loaded ultra-high-lift low pressure turbine(LPT) blade at low Reynolds number(Re) in steady state. The objective is to investigate the effect of blade roughness on the performance of LPT blade. The roughness is used as a passive flow control method which is to reduce total pressure loss and expand LPT operating margin. The experiment is performed on a low-speed cascade facility. 3 roughness heights and 3 deposit positions are investigated in the experiment which forms a large test matrix. A three-hole probe is used to detect flow aerodynamic performance and a hotwire probe is used to detect the characteristic of suction boundary layer. Regional roughness can suppress separation loss and bring fairly low turbulent dissipation loss. Detailed surveys near the blade surface shows that the loss reduction is due to the disappearance of separation bubble from the early transition onset.

关键词： Separation control Turbine blade Surface roughness

Numerical Investigation of the Bowed Stator Effects in a Transonic Fan at LowReynolds Number

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Journal of Thermal Science 2017年第1期26卷 25-29页

作者： HUANG Enliang zhao shengfeng GONG Jianbo LU Xingen ZHU Junqiang Key Laboratory of Light-duty Gas-turbine Institute of Engineering Thermophysics Chinese Academy of Sciences Bei-jing 100190 China

The performance of fan stage in a small turbofan engines is significantly affected at high-altitude low Reynolds number. In order to examine the effect of low Reynolds number on the fan stage, 3D numerical simulation method was employed to analyse the performance variations and the underlying flow structure in the fan stage. For the sake of decreasing the influence of low Reynolds number, the different bowed stator airfoils were redesigned and the effect of the modified design was evaluated.

关键词： Transonic Fan Low Reynolds Number Bowed Stator

Investigation on Multiple Cylindrical Holes Casing Treatment for Transonic Axial Compressor Stability Enhancement

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Journal of Thermal Science 2014年第4期23卷 346-353页

作者： YANG Chengwu zhao shengfeng LU Xingen HAN Ge ZHU Junqiang Key Laboratory of Light-duty Gas-turbine/Institute of Engineering Thermophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

Casing treatment is one possible way of regaining axial compressor operating range. However, most of casing treatments extend the operating range with the cost of efficiency penalty. A new form of multiple cylindrical holes casing treatment(MHCT) with pre-swirl blowing for the NASA Rotor-37 has been designed based on profound understanding of the stall inception. Unsteady numerical simulations have been performed for Rotor-37 with and without MHCT. Parametric studies of the total extraction holes area and their axial locations show that the compressor performance deteriorates as the area ratio increases but the stall margin is extended and there is an optimum extraction holes axial location for stall margin extending. The better configuration of MHCT could extend the stall margin by 6.2% with only 0.23% peak efficiency reduction. Detailed analysis of the physical mechanism behind the stall margin improvement shows that the casing treatment could eliminate the passage blockage by suppressing breakup of tip leakage vortex and decrease the blade load in tip region, which both contribute to improve stall margin of transonic axial compressors.

关键词： Casing treatment Transonic axial compressor Stall margin extending Numerical simulation

Numerical Investigation of Centerline Curvature Effects on a Compact S-shaped Intake

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Journal of Thermal Science 2012年第5期21卷 413-419页

作者： Enliang Huang shengfeng zhao Zhijun Lei Jianxiong Kang Xingen Lu Junqiang Zhu Key Laboratory of Light-duty Gas-turbine Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190 China University of Chinese Academy of Sciences Beijing 100190 China

Taking into account stealth, structure and maintenance, ultra-compact S-shaped intake has been widely used in modem vehicles. In this paper a series of steady numerical simulation were carried out to investigate the complex flow mechanism in s-shaped intake, particular attention was given to examining the effect of centerline curvature on the performance and flowfield of an ultra-compact S-shaped intake. In order to validate the multi-block model, the computational results for Royal Aircraft Establishment intake 2129-M2129 which had modest centerline cur- vature distribution were corrected with available experimental test data. The numerical simulation results agreed fairly well with the experimental data, and the computational method was then used to investigate the effects of different centerline curvature distributions on performance and flow field in compact S-shaped intake. Detailed analyses of the flow visualization had exposed the different flow topologies between the cases with different cen- terline curvature. It was found that different centerline curvature distributions changed the initial location and the size of separation bubble, as well as the strength of two counter-rotating vortices at the entrance of engine.

关键词： S-shaped Intake Secondary Flow Centerline Curvature Separation bubble Counter-rotating Vortices

Inducer/Exducer Matching Characteristics inside Tandem Impellers of a Highly Loaded Centrifugal Compressor

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Journal of Thermal Science 2020年第4期29卷 928-944页

作者： LI Ziliang zhao shengfeng LU Xin’gen HAN Ge YANG Chengwu ZHU Junqiang Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

A centrifugal compressor usually operates with low isentropic efficiency and a terrible stable operating range, resulting from the complex impeller flow structure companied with the intense interaction among the impeller and the diffuser downstream. In many studies, the potential of centrifugal compressor tandem-impeller configurations for improving the compressor has been demonstrated. Whereas, compared with the convincing results on the tandem-designed axial compressors, the results on tandem impellers are limited and contradictory. Very little insight has been provided into the flow mechanisms inside tandem impellers, which is considered to be the primary reason for the confusion in tandem impeller design and application. Tandem impellers are expected to exhibit a totally different behavior due to the intense aerodynamic interaction between the inducer and the exducer, which substantially contributes to the flow structure and the compressor performance change. In the present study, a numerical study of a highly-loaded centrifugal compressor with various tandem designs was conducted to explore the inducer/exducer matching characteristics and the underlying flow mechanism inside tandem impellers. Two tandem impeller design parameters, namely, the inducer/exducer clocking fraction and the axial gap(overlap), were considered in the tandem impeller design process. The tandem impeller was also compared to the existing conventional impeller which the tandem impeller was redesigned for. The results demonstrated that the tandem-designed impeller can improve the centrifugal compressor stage performance and intense inducer/exducer interaction can be observed with changes in the clocking fraction and the axial gap(overlap). The tandem impeller performance is sensitive to changes in axial gap(overlap) when the suction side of the exducer blade is circumferentially close to the inducer blade. The fundamental reason for the performance variation in the inducer and the exducer l

关键词： highly loaded centrifugal compressor tandem impeller inducer/exducer matching flow mechanism Kutta condition

Effects of surface roughness on the aerodynamic performance of a high subsonic compressor airfoil at low Reynolds number

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Chinese Journal of Aeronautics 2021年第3期34卷 71-81页

作者： Mingyang WANG Chengwu YANG Ziliang LI shengfeng zhao Yanfeng ZHANG Xin’gen LU Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The aerodynamic performance of compressor airfoil is significantly affected by the surface roughness at low Reynolds number(Re).In the present study,numerical simulations have been conducted to investigate the impact of surface roughness on the profile loss of a high subsonic compressor airfoil at Re=1.5×10^(5).Four roughness locations,covering 10%,30%,50%and 100%of the suction surface from the leading edge and seven roughness magnitudes(Ra)ranging from 52 to525 lm were *** showed that the surface roughness mainly determined the loss generation process by influencing the structure of the Laminar Separation Bubble(LSB)and the turbulence level near the *** all the roughness locations,the variation trend for the profile loss with the roughness magnitude was *** the transitionally rough region,the negative displacement effect of the LSB was suppressed with the increase of roughness magnitude,leading to a maximum decrease of 14.6%,16.04%,16.45%and 10.20%in the profile loss at Ra=157 lm for the four roughness locations,***,with a further increase of the roughness magnitude in the fully rough region,the stronger turbulent dissipation enhanced the growth rate of the turbulent boundary layer and increased the profile loss *** comparison,the leading edge roughness played a dominant role in the boundary layer development and performance *** take fully advantage of the surface roughness reducing profile loss at low Re,the effects of roughness on suppressing LSB and inducing strong turbulent dissipation should be balanced effectively.

关键词： Aerodynamic performance Compressor airfoil Low Reynolds number Separation bubble Surface roughness Viscous dissipation

Effect of Non-Axisymmetric End Wall on a Highly Loaded Compressor Cascade in Multi-Conditions

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Journal of Thermal Science 2021年第4期30卷 1363-1375页

作者： HUANG Song YANG Chengwu LI Ziliang HAN Ge zhao shengfeng LU Xin’gen Key Laboratory of Light-duty Gas-turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

As an effective method to influence end wall flow field,non-axisymmetric profiled end wall can improve the aerodynamic performance of compressor *** a highly loaded low pressure compressor cascade,called V103,the study found the optimal non-axisymmetric profiled end wall decreases total pressure loss coefficient by 4.57%,5.48%and 3.04%under incidences of–3°,0°,and 3°,respectively,compared with those of the planar end *** optimal non-axisymmetric profiled end wall changes the structure of secondary flow in hub region,generating a corner vortex near suction surface,inhibiting the development of the passage vortex towards suction surface and reducing flow *** the inlet Mach numbers are 0.62 and 0.72,the total pressure loss coefficient decreases by 3.19%and 4.58%for optimal non-axisymmetric profiled end wall compared with those of the planar end *** optimal non-axisymmetric profiled end wall increases total pressure loss near hub region in blade passage under different inlet Mach numbers,the peak value and region of high loss coefficient above 10%span in blade passage significantly *** addition,different incidences affect the secondary flow streamlines and vortex structure near the cascade hub region,however,different inlet Mach numbers hardly change the secondary flow streamlines and vortex *** short,the optimal non-axisymmetric profiled end wall shows better aerodynamic performance than the planar end wall for the highly loaded compressor cascade in multi-conditions.

关键词： non-axisymmetric profiled end wall total pressure loss highly loaded compressor cascade passage vortex